Method and apparatus for handling sheet material, signatures and the like

ABSTRACT

Apparatus for feeding signatures from a stack thereof in gathered predetermined sequence to a book-sewing machine or the like, comprising means for transferring signatures one at a time from a feed hopper by rotary grippers and feed rollers to linearly traveling grippers, suction and lap-engaging means for opening signatures suspended from the traveling grippers, and means for rotating the suspended, opened signatures through 180* and depositing the same on a pusher-type saddle conveyor for movement thereby through fold-conditioning means and for delivery to the sewing saddle of a book sewer or the like, including operational programming means for the feeding and sewing apparatuses and means for detecting improper functioning thereof.

1,845,412 2/1932 Hathaway United States Patent [72] inventors John 0. McCahon West Simsbury, Conn.; William J. Byrne, Pearl River, N.Y. [2t 1 Appl. No. 706,926 [22] Filed Feb. 20, I968 [45] Patented July 6, I971 [73] Assignee North American Rockwell Corporation Pittsburgh, Pa.

[54] METHOD AND APPARATUS FOR HANDLING SHEET MATERIAL, SIGNATURES AND THE LIKE 46 Claims, 38 Drawing Figs.

[52] U.S. Cl 270/54 [5 l] Int. Cl B65h 39/02 [50] Field of Search 270/54, 55

[56] References Cited UNITED STATES PATENTS 3,311,368 3/l967 Sarringetal... 3,420,516 1/1969 Guggisberg ABSTRACT: Apparatus for feeding signatures from a stack thereof in gathered predetermined sequence to a book-sewing machine or the like, comprising means for transferring signatures one at a time from a feed hopper by rotary grippers and feed rollers to linearly traveling grippers, suction and lap-engaging means for opening signatures suspended from the traveling grippers, and means for rotating the suspended, opened signatures through 1800 and depositing the same on a pusher-type saddle conveyor for movement thereby through fold-conditioning means and for delivery to the sewing saddle of a book sewer or the like, including operational programming means for the feeding and sewing apparatuses and means for detecting improper functioning thereof.

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'SHEET 1; OF 17 iqJZi TNVENTORS JOHN 0. MCAHON E 7 BY WILLIAM J. BYRNE Edda MW ATTORNEYS PATENTEU JUL BIS?! 3,591; 165

SHEET 18 0F 17 INVENTORS JOHN 0. women BY WILLIAM J. BYRNE ATTOR EYS PATENTEDJUL 6|97l 3.691.165

SHEET 17 0F 17 k mo INVENTORS W///////////////////////// wgmrg ATTO NEYS The present invention relates to a method and apparatus for automatically handling sheet material, signatures and the like.

One of the objects of the present invention is to provide novelly constructed means for handling folded signatures in a novel manner.

Another object of the invention is to provide novel apparatus whereby folded signatures are transferred from a rotary or planetary conveyor to conveyor means for supporting the signatures in suspension and moving the same edgewise in a direction parallel to the axis of the rotary conveyor.

Another object is to provide novel simplified mechanism for separating the pages of and hence, opening a signature while thesame is in motion and suspended with backbone fold uppennost.

A further object is to provide novel apparatus for controlling the sequential operation of a plurality of functional mechanisms of a machine for handling signatures and the like.

Still another object is to provide novel apparatus for turning an opened signature end-for-end withoutpermitting closure thereof while the same is being simultaneously linearly con veyed.

A still furthe'r'object isto'provide novelly constructed apparatus for acting'on a fold of sheet material, such as the backbone fold of a signature, to condition the same for a 'snugger fit on and better seating on the apex of the saddle of a conveyor or book-sewing machine.

' Another object is to provide novel simplified apparatus for automatically withdrawing flat closed signatures from an onedge stack and transferring the same to a saddle conveyor in open condition.

The above and further objects and. novel features of the present invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition of the limits of the invention.

. In the drawings, wherein like reference characters refer to like parts throughout the several views, I

FIG. I is a partially diagrammatic front elevation view of one form of apparatus embodying the invention;

FIGS. 2, 3, and 4 are isometric views illustrating some representative forms of signatures which the apparatus of FIG. 1 is adapted to handle;

FIG. 5 is a partial end elevation view of the apparatus as seen from lines 5-5 of F IGS..1 and 6 with the guard removed;

FIG. 5a is a detail view taken on line 5a-5a of FIG. 5;

FIG. 6 is a partial top plan view of the inserter or feeder section of the apparatus taken substantially on line 6-6 of FIG. 5;

FIG. 7 is an elevation view, partly in section, taken on line 7-7 of FIG. 6;.

FIGS. 8 and 9 are detail views taken on line 8-8 of FIG. 6 and showing the parts in different cyclic positions following the positions thereof shown in FIG. 7;

FIG. 10 is a detail elevation view, partly in section, taken on line 10-10 of FIG. 6;

FIG. 11 is a detail sectional view of one suitable form of signature-gripping device, the section being taken on line 11-11 of FIG. 13a;

FIGS. 12 and 120 are complementary top plan views with parts broken away of opposite ends of the gripper conveyor C as viewed from the top in FIG. I and FIGS. 13 and 13a,

respectively; I

FIGS. 13 and 13a are front elevation views partially in section taken substantially on lines 13-13 and 13a-13a of FIG. 12 and FIG. 12a, respectively;

FIG. 14 is a sectional view taken on line 14-14 of FIG. 13;

FIG. 15a, 15b and 15c are diagrams illustrating successive positions of agripper device as viewedfrom the plane of line FIG. 16 is a partial top plan view from the plane of line 16-16 of FIG. 1 showing one suitable form of apparatus for opening signatures on the run;

. FIG. 17 isa detail elevation view, partly in section taken on lines 17-17 of FIGS. 1 and 16;

FIG. 18 is a detail isometric view of the signature turnaround saddle;

FIG. 19 is a detail top plan view of the pusher saddle conveyor B with parts broken away, the view being taken on line 19-19 of FIG. 1;

FIG. 20 is a detail sectional view taken substantially on line 20-20 of FIG. 19;

FIG. 21 is a detail sectional view taken on line FIG. 19;

FIG. 22 is a partial end elevation view taken substantially on line 22-22 of FIG. 1; 7

FIG. 23 is a detail side elevation view taken on line 23-23 of FIG. 22;

FIG. 24 is a detail view partly in section taken substantially on lines 24-24 of FIGS. 19 and 22;

FIG. 25 is a detail side elevation view partly in section taken on line 25-25 of FIG. 22;

FIG. 26 is a detail sectional view taken on line 26-26 of FIG. 1;

FIG. 27 is a partial front elevation view partlyv in section taken on line 27-27 of FIG. 29; I

FIG. 28 is a detail sectional view taken on line 28-28 of FIG. 27;

FIG. 29 is essentially a detail top plan view taken on lines 29-29 of FIGS. 1 and 27;

FIG. 30 is a detail isometric view illustrating several links of a programmer belt; FIG. 31 is a detail sectional view taken on line 31-31 of FIG. 1;

FIG. 32 is a detail side elevation view of the vacuum valve unit of the programmer as viewed from line 32-32 of FIG. 29; and

FIG. 33 is a sectional view taken on line 33-33 of FIG. 32.

One embodiment of novel apparatus adapted for use in practicing the novel method contemplated by the invention is illustrated in front elevation, partly diagrammatically, in FIG. 1 of the drawings. This apparatus is capable of handling closed head right-angle signatures (FIG. 2), inserted signatures (FIG. 3), open head signatures with front lap (FIG. 4) and a variety of other lap and no-lap signatures with or without end sheets, cutaways, tips and the like. Speaking generally, the illustrated machine as shown in-FIG.'l comprises ahopper-type rotary signature feeder F which transfers signatures one at a time from an on-edge stack S to an endless conveyor C equipped with a series of grippers G. The signatures are transported by conveyor C in suspended on-edge position through a signature-opening section 0 controlled in part by a programmer P and then through a signature-tuming section T before being dropped astraddle a pusher-type saddle conveyor B. The latter moves the signatures through a backbone fold conditioner R and thence to the infeed saddle conveyor (not shown) of a known type of book-sewing machine, such as the Smyth No. 12 sewing machine. The entire signature-handling machine is powered by a motor through a main drive shaft D, and the sewing machine is preferably powered by the same motor in predetermined timed relation to the signature-handling machine.

HOPPER FEEDER AND TRANSFER MECHANISM I (FIGS. 1 to 10) The novel apparatus contemplated by the invention for handling folded signatures and delivering the same to a saddle conveyor, book-sewing machine or the like in accordance with a novel method comprises a novel hopper-type signature feeder. One form of such feeder is illustrated, by way of example, in FIGS. 5 to 10 as having a supporting frame comprising end plates 1, 1' on which is mounted signature hopper I-I that may be of any suitable known construction. A stack S of signatures gathered in the order or sequence in which the same are to be sewn together in book form is supported on-edge by slightly inclined bars 2 and endless belts 3 and rests forwardly against a plate 4 (FIGS. 6 and 7). The folded backbone edges 6 of the signatures 5 in stack S, which edges will constitute the sewn spine of the book, should be down, and the closed ends or heads 7 of the signatures should be toward the left and hence, the leading edge in FIG. 1 of the illustrated embodiment. The bottom edge of the leading signature, at the right in stack S as viewed in FIG. 7, may engage adjustable stops 8, and as signatures are withdrawn one at a time from the forward end of the stack, the latter may be moved forwardly against stops 8 by intermittent operation of belts 3 in a manner well known in the art, such as by the cam-actuated linkage L shown in FIG. 10.

Novel means are provided for withdrawing the leading signature 5 from stack S and transferring the same to the continuously operating endless gripper conveyor C in suspended inverted position, i.e. with the backbone fold 6 uppermost, and the open edge portions of the signatures freely suspended from the conveyor grippers G. In the form shown, said means comprises a shaft 9 rotatably supported in plates 1, l and driven by power means M in a counterclockwise direction, as seen in FIGS. 5 and 7, through a gear train including gears 10, II and timing belt 12 (FIG. 5) which is driven from main power shaft D. I

In a conventional manner, the lower edge 6 of each signature in stack 8 is engaged and drawn to the right below plate 4 (FIG. 7) by a plurality of vacuum suckers 13 of known construction mounted on stub shafts 14, 14 for pivotal reciprocation as indicated by arrows. Timed operation of the suckers and linkage L is efi'ected by a disc cam 15 driven by shaft 9. The suckers are carried on hollow arms I6 mounted on and projecting radially from a hollow bar 16, the ends of which are carried by arms 17, I7 pivotally mounted on said stub shafts I4, 14'. A lever 18 integral with arm 17 carries a cam follower roller 18 which is held in engagement with cam 15 by suitable resilient means,'such as a spring 15 connected to lever 18 (FIGS. 6 and The cups or heads of suckers 13 are connected to a source of vacuum at appropriate intervals and in timed relation with the other functions of the apparatus through hollow arms 16', hollow bar 16, a flexible hose 20, a rotary disc valve 21 concentric with and driven by shaft 9, and a flexible hose (notshown) leading from the valve to a source of vacuum, such as a motor driven pump 19 (FIG. I) all in a manner well known in the art.

The lower edge 6 of a signature 5 withdrawn by vacuum suckers 13 (FIG. 7) is then engaged by mechanical or suctiontype gripper means carried by shaft 9 in a known manner. In the form shown, a plurality of mechanical grippers are mounted on a plurality of discs 22, 22 which may be identical and in effect constitute a drum. The discs 22 are in turn mounted on shaft 9 for rotation therewith and constructed to perform a dual function. Said gripper means comprises blocks 23 mounted on drum discs 22 near the periphery thereof and having arcuate gripping surfaces that form lateral extensions of the peripheral or rim surfaces of the discs for cooperation with gripper fingers 24 fixedly mounted on a shaft 25 that is eccentrically journaled in discs 22 and a disc 26 on shaft 9 for angular reciprocation relative thereto. A pinion 27 on one end of shaft 25 meshes with a gear segment 27' which forms one arm of a bellcrank pivotally mounted at 28 on disc 26 which rotates with shaft 9. The gear segment 27', carries a roller 29 which is held in engagement with a cam 29 by a compression spring 30 connected to the other arm of the bellcrank, said cam being secured to frame 1. Thus, at the proper time in the cycle of counterclockwise rotation of drum 22, 22, as viewed in FIGS. 7 to 9, gripper fingers 24 are moved into cooperative relation with blocks 23 togrip the lower edge 6 of a signature 5 which, sis-assessed above, has been segregated from the stack S bysq'ckers' 13 (FIG. 7). Upon continued rotati'on of drum 22', 22"t'he gripped signature is withdrawn downwardly from the stack and carried in an arcuate path by the drum (FIG. 8). j i 4 1 In addition to carrying gripper means 23 24 for removing and conveying signatures from stack S, the drum 22, 22 cooperates with a sector drum 31 to provide a friction or rolltype sheet or signature feeder to which signatures are delivered'by said gripper means. In the form illustrated, sector drum 31 also consists of a plurality of discs which mate with the discs of the first drum 22, 22. As shown, the latter may also be a sector drum; that is, a drum having only a sectoral rim or peripheral surface of maximum diameter. Drum'3l bomprises two identical sector discs mounted on a shaft 32 for rotation therewith. Said shaft is parallel to shaft 9 and is preferably driven by a gear 32 which is in constant mesh with drive gear 1 l on shaft 9, whereby drums 22 and 31 are driven in opposite directions as indicated by arrows in FIG. 8.

Shaft 32 is journaled near its end in corresponding arms 33 of bellcranks 33, 33 which are pivoted on a transverse crossbar 34 between the main frame plates 1, l. The bellcranks 33, 33' are resiliently urged in a counterclockwise direction as viewed in FIGS. 5 and 10 by compression springs 35 interposed between the arms 33' of the bellcranks and fixed brackets 35'. Said springs urge arms 33' against adjustable stops 36 which determine the minimum clearance between the sectoral rim surfaces a and b of drums 22 and 31, respectively. Suitable known means including a threaded member 36' may be provided for adjusting the compression of each spring 35 and thereby the pressure applied to a signature gripped between the sectoral surfaces a and b of the cooperating drum discs 22 and 31. r Y

The sectoral rims (and b of sector drums 22 and 31 may but need not be of equal radius. The rotationalvelocities of the two drums are, however, so chosen that the sectoral surfaces thereof are face-to-face when passing through the plane containing the drum axes (FIG. 9) at the same time-to bite or grip a signature 5 therebetween under the pressure of springs 35 and to thus frictionally feed the signature upwardly. The relative speeds of rotation of the two drums 22 and 31, as determined by the diameters of drive gears 11 and 32, are such that the linear speed of the sectoral rim surfaces a and b which engage opposite sides of the signatures are substantially equal.

Thus, when the leading edge 6 of a signature 5 engaged by gripper means 23, 24 has been moved from the position illustrated in FIG. 8 to the plane containing the parallel axes of shafts 9 and 32, the adjacent sectoral surfaces a and b will cooperate to bite .and frictionally grip the edge 6 of the signature while at about the same time, cam 29' will operate to actuate gripper fingers 24 to open position (FIG. 9) and thus release said edge of the signature. Following such release the signature is fed upwardly by drums 22 and 31 and is preferably guided by a plurality of stationary depending bars 37 in inverted position from that which it occupied in the hopper II. The now upper edge 6 of the signature, which may be the backbone fold thereof, is directed into one of a plurality of gripper mechanisms G of the endless conveyor C to be next described. Each gripper G, as it passes above drums 22 and 3l, is moving continuously and horizontally toward the left (FIG. 1) in a line parallel to the axes of said drums and perpendicular to the direction in which the signature is being fed by said drums. The timing of the cooperating mechanisms is such that an open gripper G receives the edge of the signature and closes to support and convey the same in suspended position (FIG. 7) at the same time that the signature is released from the grip of drums 22 and 31; that is, when the trailing end of at least one of the sectoral rim surfaces 0 and b moves above the plane containing the axes of said drums, thereby freeing the signature for movement in a line parallel to said axes toward the signature-opening section 0. The discs making up drum 31, 31 are preferably angularly adjustable on shaft 32 

1. In apparatus for handling sheetlike material, such as folded signatures, means for gripping a signature at a folded edge thereof and transporting the same in an arcuate path, a pair of continuously rotating drums for receiving and gripping said edge and roll feeding the signature upwardly in a generally vertical plane with said edge uppermost, continuously moving endless conveyor means, gripper means mounted on said conveyor means and movable horizontally thereby in said plane, means for opening said gripper means to receive said edge of the upwardly fed signature, means for closing said gripper means on said edge when the signature is released by said drums, means for opening a signature suspended from said moving gripper means, means for turning said gripper means with an opened signature relative to the conveyor means, means for holding the signature open while the same is being turnEd with the gripper means, and inverted Vshaped saddle, means for opening said gripper means to release the opened signature to drop astraddle said saddle with said folded edge uppermost, means for pushing the signature along said saddle, and means for compressing the fold at said edge of the signature as the same is moved along said saddle, said last-named means comprising a rotatable disc extending through a slot in the apex of the saddle within the signature and a wheel with a Vshaped peripheral groove engaging the outer surface of said folded edge.
 2. Apparatus for handling folded signatures comprising a first rotatable drum, a second rotatable drum adjacent to and cooperable with said first drum to grip and frictionally feed a signature edgewise in a plane, first gripper means revolvable with said first drum for conveying a signature edgewise in a path corresponding generally with the outer peripheral surface of said first drum and into the bite of said drums, means for opening the first gripper means to release the signature when the latter is gripped between said drums, endless conveyor means including second gripper means for receiving the leading edge of a signature fed by said drums and conveying the same edgewise in said plane in a direction normal to the direction in which the signature is fed by said drums, and means mounted adjacent the path of movement of the signature by said conveyor means for opening the advancing signature in response to the advancing movement of the signature.
 3. Apparatus as defined in claim 2 wherein said means for opening the signature comprises suction gripper means for initiating the opening of the advancing signature.
 4. Apparatus as defined in claim 2 wherein said means for opening the signature comprises stationary means for plowing the advancing signature open to its center.
 5. Apparatus for handling folded signatures as defined in claim 2 wherein the advancing signature is gripped at its folded edge by and loosely suspended from said second gripper means.
 6. Apparatus as defined in claim 5 for handling lapped signatures wherein said signature-opening means is stationary and extends across the path of the lap of the signatures.
 7. Apparatus for handling folded signatures and the like comprising means for conveying a folded signature edgewise in suspended condition with its backbone folded edge uppermost, and suction-gripping means for opening the signature to its center by separating some of the suspended sheets of the signature from the remainder at the edge opposite said folded edge while the signature is advanced by said conveying means, said gripping means including a device rotatable about a fixed axis beside the path of the moving signature.
 8. Apparatus as defined in claim 7 wherein said axis converges upwardly at an acute angle with the plane of the path of the signature suspended from the conveying means.
 9. Apparatus as defined in claim 7 wherein said device comprises reciprocable gripper means for engaging and gripping the suspended signature sheet or folio adjacent said device.
 10. Apparatus as defined in claim 9 wherein said gripper means are cyclically linearly reciprocable along an axis substantially normal to the plane of the broad surface of the signature.
 11. Apparatus as defined in claim 9 wherein said gripper means reciprocate along an axis extending generally radially of and at an acute angle relative to said fixed axis.
 12. Apparatus as defined in claim 9 wherein said device comprises rotary valve means for alternately connecting the reciprocable gripper means to a source of vacuum and to atmosphere during predetermined portions of each revolution of said device.
 13. Apparatus as defined in claim 9 wherein said reciprocable gripper means is mounted to reciprocate in a line making an acute angle with said fixed axis.
 14. Apparatus as defined in claim 9 wherein said reciprocable gripper means are fluid pressure actuated.
 15. Apparatus as defined in claim 9 compriSing means for continuously driving said conveying means and said device in timed relation so that the signature-engaging surface of said gripper means is revolving in an arcuate path substantially tangent to the surface of the leading edge portion of the passing signature when it engages the latter.
 16. Apparatus as defined in claim 9 wherein said device comprises an arcuate member tangentially engageable with the signature in the wake of the reciprocable gripper means.
 17. Apparatus as defined in claim 9 comprising backup means in the line of the signature engaging reciprocating movement of said gripper means and positioned on the side of the path of the signature opposite the signature opening means.
 18. Apparatus as defined in claim 1 wherein said signature opening means comprises a stationary guide bar extending longitudinally of the path of the signature and shaped to be engaged by said separated sheets when the same area released by said gripper means for further separating the sheets from the remainder of the signature in response to movement of the signature by the conveying means.
 19. A method of handling folded signatures which comprises the steps of suspending a signature with the backbone fold thereof uppermost, conveying the suspended signature edgewise, gripping the lower leading edge portion of the outer sheet or folio of the suspended advancing signature with revolving reciprocable means to retard said sheet or folio and withdraw the same from the path of movement of the remainder of the signature, and plowing the withdrawn sheet or folio upwardly and away from said path in response to the advancing movement of the suspended signature to thereby open the latter.
 20. A method as defined in claim 19 wherein the signature is suspended from a continuously moving gripper and further comprising the step of roll feeding the signature to the gripper in a direction at right angles to the direction of movement of the gripper.
 21. A method of opening a lapped signature which comprises suspending the signature with its lapped edge lowermost, moving the suspended signature edgewise in a plane parallel to the broad surfaces of the signature and in a direction parallel to said lapped edge, and plowing the lapped half of the signature out of said plane in response to the movement of the signature to open the latter to its center.
 22. The method of handling signatures which comprises the steps of gripping the backbone edge of a signature and withdrawing the same downwardly from a stack of signatures on edge, conveying the signature along a curved path to invert the same, releasing said edge and, without interrupting the advance thereof, simultaneously roll feeding the signature upwardly with said edge uppermost, simultaneously interrupting the roll feeding of the signature and gripping said edge by a continuously moving gripper to support the signature in suspension and continuously advance the suspended signature edgewise horizontally, opening and advancing suspended signature, and releasing the opened signature to drop a straddle a saddle.
 23. The method as defined in claim 22 which includes the step of turning the advancing opened signature end-for-end before releasing the same onto the saddle.
 24. The method defined in claim 22 wherein the step of opening the signature is to a substantial degree effected in response to the advancing movement of the signature.
 25. The method as defined in claim 22 wherein the step of opening the signature is effected by plowing a lapped half of the signature away from the remaining half thereof in response to movement of the advancing signature.
 26. Apparatus for opening folded signatures comprising means for conveying a signature edgewise in the plane of the broad surface thereof and suspended with the backbone folded edge thereof uppermost, means for separating depending sheets of said signature as the same is advanced by the conveying means including a suction gripper head revolvable about a fixed axis beside Said plane, means for revolving said gripper head, means for connecting said gripper head to a source of vacuum, means for projecting the revolving-gripper head generally radially from said axis into gripping engagement with a side surface of the signature adjacent the lower and leading edges thereof and for retracting said revolving-gripper head with the portion of the signature thus gripped by said head, means for disconnecting said gripper head from said source of vacuum to effect release of said gripped portion of the signature, and means for maintaining said portion of the signature separated from the remainder thereof as the signature is advanced by the conveying means.
 27. Apparatus as defined in claim 26 wherein said gripper head is mounted to revolve in a plane inclined from the plane of movement of the signature whereby said revolving-gripper means lifts the lower edge of the gripped sheet of the signature while simultaneously withdrawing it from the remaining depending sheets.
 28. Apparatus as defined in claim 26 wherein said gripper head is revolved at a speed approximately equal to the linear speed of the advancing signature.
 29. Apparatus for opening folded signatures comprising a stationary frame, a supporting beam mounted on said frame, means mounted on the frame for conveying a suspended signature edgewise in a path above and along said beam, and means comprising rotatable, radially reciprocable gripper mechanism mounted on said beam for engaging a moving signature and diverting a portion thereof at one side of the center thereof away from said path to thereby open the signature.
 30. Apparatus as defined in claim 29 wherein said rotatable gripper mechanism includes suction gripper means.
 31. Apparatus as defined in claim 29 comprising drive means mounted on the frame and operably connected with said gripper mechanism for rotating the same.
 32. Apparatus as defined in claim 31 comprising means for adjusting said beam vertically relative to said drive means and said conveying means.
 33. Apparatus as defined in claim 29 comprising a plurality of said last-named means on each side of said path, and means for selectively rendering each of said plurality of means operable for diverting a portion of a passing suspended signature to open the same.
 34. Apparatus as defined in claim 29 wherein said last-named means comprises a plurality of suction grippers mounted on each side of said path in spaced relation to each other, the grippers on each side being successively operable to engage an advancing signature.
 35. Apparatus as defined in claim 34 comprising programming means driven in synchronism with the signature conveying means for selectively controlling the operation of each of said suction grippers.
 36. Apparatus for opening folded signatures comprising a stationary frame, a supporting beam mounted on said frame, means mounted on said frame for conveying a suspended signature edgewise in a path above and along said beam, and means mounted on said beam for engaging a moving signature and diverting a portion thereof at one side of the center thereof away from said path to thereby open the signature, said last-named means comprising a member extending across said path at an acute angle thereto for engagement by the lowermost marginal portion of a depending part of an advancing lapped signature.
 37. Apparatus as defined in claim 36 wherein said member is inclined upwardly away from said path at one side thereof.
 38. Apparatus as defined in claim 36 comprising means mounted on said beam for selectively moving said member into and out of operative position across said path.
 39. Apparatus for feeding signatures one at a time in spaced relation to a book-sewing machine or the like from a stack of folded signatures of varying composition flat gathered in a stack in predetermined book-forming sequence, said apparatus comprising a continuously operating, endless conveyor including a series of equally spaced signature grippers and haviNg a lower horizontal reach from which the grippers depend, rotary means for withdrawing signatures one at a time from said stack, roll feed means for receiving said signatures from said rotary means and delivering the same upwardly into said grippers traveling with said horizontal reach of the conveyor, said grippers engaging an edge portion of the signatures while supporting and transporting the same edgewise in suspension, means for opening each signature to its center while the same is advanced by said conveyor, and means for continuously driving said conveyor, rotary means, roll feed means and said signature opening means in predetermined timed relation.
 40. Apparatus as defined in claim 39 comprising programming means for selectively controlling said signature opening means in accordance with the composition and sequence of the signatures being fed from said stack, said programming means being driven by said driving means in timed relation with the feeding of the signatures.
 41. Apparatus as defined in claim 39 comprising means for rotating said depending grippers relative to the conveyor together with the opened signatures suspended therefrom.
 42. Apparatus as defined in claim 39 comprising a saddle conveyor, and means for actuating said grippers to release opened signatures to drop onto said saddle conveyor.
 43. Apparatus as defined in claim 42 comprising means disposed intermediate the ends of said saddle conveyor for compressing the backbone folds of the signatures, said compressing means including intermeshing rollers engaging the inner and outer surfaces of said folds.
 44. Apparatus as defined in claim 43 comprising resilient means for urging said rollers into compressing relation with said folds.
 45. Apparatus as defined in claim 39 wherein said signature-opening means comprises at least one suction gripper for initiating the opening of a signature and a guide rod for completing such opening in response to movement of the signature by said conveyor.
 46. Apparatus as defined in claim 39 wherein said signature-opening means comprises at lease one member extending across the path of the advancing signatures for engagement by the depending lap portion of a lapped signature. 